Combined binding post and thermal out-octt



(No Model.)

H. G. ROOT. COMBINED BINDING POST AND THERMAL GUT-OUT. No. 413,813.Patented 001:. 29. 1889.

I H! '10 i 13 I a l I f; k\ A WITNESSES:

N. PETERS. Pnm-umu mnu .mmmen. By C UNITED STATES PATENT OFFICE.

IIOWZARD C. ROOT, OF BROOKLYN, NEW YORK, ASSI NOR OF ONE-HALF TO JOHN G.REILLY,

OF SAME PLACE.

COMBINED BlNDlNG-POST AND THE RMAL CUT-OUT.

SPECIFICATION forming part of Letters Patent N 0. 413,813, dated October29, 1889.

Application filed June 1 7 l 88 9.

T aZZ whom, it may concern.-

Be it known that I, HOWARD 0.13001, a citizen of the United States,residing at Brooklyn, in the countyof Kings and State of New York,

have invented certain new and useful 1mprovements in Binding-Posts forElectric Circuits; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled IO in the art to which it appertains to make and use thesame.

This invention relates to a novel form of lightning-arrester orinstrument-protector for use in such electric circuits as require thepresence of a fusible connection of such character as to be fused by theaction of at current in excess of the normal current which is supposedto fiow in such circuit.

This invention comprises a combined proteeter and binding-post, andfurther coinprises the construction and combination of parts,substantially as hereinafter fully set forth, and pointed out in theclaims. I

In the drawings which form part of this specification, Figure 1 is aside elevation of the complete structure when self-contained.

Fig. 2 is a vertical section of the same with the cap removed, showingthe selfejecting tendency of the fuse-carrier. Fig. 3 is a detached viewof the fuse-carrier. Fig. i is a sectional view of the device when abaseboard is substituted for the insulating-stem of Fig. i.

I construct as follows, the metallic parts being preferably made ofbrass, as is usual in the case of binding-posts and other electricalapparatus: The insulating portions may be hard rubber, vulcanized fiber,or any other material having the necessary qualities of insulation andmechanical strength. Starting with the brass shank 1,which is providedwith a collar 2, integral therewith and having the threaded portions 3and 4, respeetively,l place on the threaded portion 3 the clampingnut 5,for the purpose of affording a point of convenient attachment for theline or other wire to be connected to the device. Upon the threadedportion l of shank 1, I screw the block of insulating material 6, havingthe internal bore 7 and the threaded socket S in its upper end. Into thesocket 8, I screw one Serial No. 814,592. (No model.)

end of the brass nipple 9, which is provided with the flange l0 and isbored out and fitted with an internal sleeve 11, of insulating material,whose internal diameter and axis eorrespond with that of the cavity 7 inthe rubber block 6. At the bottom of cavity 7, I place a spiral spring12, which I prefer to make of German silver. Into the bore thus formedin the nipple 9 and rubber block 6, I introduce the fuse proper, whichconsists of a small tube or rod 13, of insulating material, havingmetallic tips or caps 1a 15 at its ends, and these are connectedelectrically byineans of the fuse of tin-foil or other material 16,which may he wound around the central rod or tube 13 or placed insideit. The metallic cap 17 is internallythreaded to fitthe nipple 9, and inits top is fitted the pressure-screw 18. I prefer to form the tips orcaps 1t 15 with conical or other shaped projecting ends, and the lowerend of the clamping-screw 18 is recessed to correspond, so as to guidethe fuse -carrier. The cap 17 is made of such length that its lower edgeis adapted 7 5 to form, in connection with the flange 10 of the nipple9, an effective clamping point for the circuit-wire, which is simplybentaround the nipple 9, and the screwing down of the cap 17 completes avery effective and reliable connection. IVhen the cap 17 is thus screweddown after the insertion of the fuse, the pressure-screw 18 is screwedin and makes contact with the tip or cap on the end of the fuse andpresses the lower cap of the fuse into effective contact with the upperend of the coiled spring 12, which is thus slightly compressed. The twoeircuit-terminals, which are indicated by dotted lines in Fig. 1, arethus connected through the pin 1, spring 12, o tip 15, fuse 1G, tip 14-,pressurescrew 18, and connections 10 17. I make the cap 17 polygonalexternally for use with a wrench.

Thus constructed the device forms a very compact and very reliablebinding-post and safety-cateh combined in one complete structure, whichis of small size and cheap in cost of manufacture. The fuse itself issecurely incased and thus fully protected from accidental injury fromworkmen while arranging IOO wires and from exposure to atmosphericchanges, as are also the contacts forming part of the fuse-circuit.Should the fuse melt at any time from passage of an excessive current,and thus produce a tendency in the latter to are, the latter isprevented by the external high insulation afforded by the internal tube11, of rubber.

The device has the great advantage of permitting the insertion andremoval of the fuse without disconnecting any of the wires or disturbingany of the parts other than the pressure-screw 1S, and the insertion offuse need not be made until all work of arranging wires is finished.Upon removing this screw from its position the tension of spring 12 hasthe eifect of partially or wholly ejecting the fuse 13 and its attachedcaps, so that a new one may be readily inserted, after which therestoration of the screw 18 to its position completes the circuit, asbefore.

The device affords exceptional facilities for testing. By removing thepressurescrew 18 and the fuse the two circuits or two branches I of thecircuit which terminate in the bindingpost can be separately tested, oneby contact with the binding-post portion of the structure 10 17 and theother byinserting an insulated pin in place of the fuse, such pin thenmaking contact with the spring 12, and through it with the part of thecircuit connected to the shank 1, without the necessity for disconnecting any wire whatever or using tools for the purpose of opening anycircuits or branches. This latter ad vantage is very marked when thedevice is to be used as abinding-post for insertion into a switch-boardor other structure-such, for instance, as a cable-terminal head, wherethe shank 1 and its exposed portions will be hidden and-not accessiblefor the purpose of testing; but by the above-stated use of an insulatedpin capable of reaching into the central bore and making contact withthe .spring 12 this test can be very readily made by the use of mystructure.

Obviously the fuse 16 may be of any suitable material-such, forinstance, as tin or lead foil or a thin wire-and it may be wound one ormore times around the rod 13 or may be straight thereon or insertedinside, according to the circumstances of use or the will of thedesigner. The caps 14 and 15 are utilized for the purpose of clampingthe ends of the fuse 16 in the act of placing the said caps in positionon the ends of rod 13.

Then a number of such binding'posts are to be applied to a common base,as in switchboards or distributing-boards, I prefer the form shown atFig. 4. Here the rubber block 6 is dispensed with, and the bodyorsubstance of the base 20 used instead. The shank 1 in that case isscrewed into the base 20 from the rear and the nipple 9 from the front,the bore 7 forming, as before,a communication between them and a cavityfor the spring 12. ,In the same figure I show the fuse inclosed insidethe tubular carrier 13, and this form of fuse permits me to dispensewith the insulatingsleeve 11 required in Fig; 2. In other respects theconstruction has all the advantages and conveniences of that shown inFigs. 1 and 2.

The device may be used for protective purposes on any well-known formsof electrical apparatus, but is more especially designed for directapplication to cable-terminal heads, 1nagneto-bells, and kindredapparatus, wherein it is desirable to have the binding-post combinedwith the protector and the Whole structure reduced to the most compactform possible.

I claim as my invention- 1. The combined connector and safetycatchcomprising two metallic binding-posts insulated from each other, butrigidly in line, and a non-conducting fuse-carrier having metal tipsconnected by a fusible strip and held between said posts by a spring atone end and at the other by a removable abutment-screw passing throughone of said posts in line with the fuse-carrier. I

2. The combined connector and safetycatch comprising a sleeve ofinsulating material interposed between two metal bindingposts andforming a rigid structure therewith, a metal spring in contact with onebindingpost, a removable abutment projecting from the other, and anon-conducting fuse-carrier having metal tips connected by afusiblestrip placed between said spring and abutment.

3. The combined binding-post and safety-- catch comprising, incombination, the shank 1,-provided with clamping devices, spring 11,tubular nipple 9, insulated fuse 16, screw-cap 17, and pressure-screw18, adapted to force the fuse 16 against the spring 11 and compress thelatter, said shank 1 and nipple 9 being held in fixed position in'asolid insulating material.

In testimony whereof I afiix my signature in presence of two witnesses.

